In my International patent application No PCT/AU92/00520 (AU671423), I disclose radiant solar energy collecting apparatus which includes a platform assembly floating on a body of liquid usually water contained in a reservoir, the top side of the platform assembly supporting reflectors of a solar concentrator. In the apparatus disclosed in my International patent application No. PCT/AU99/00140 (AU742755), the platform assembly can also support photovoltaic cells and the underside of the platform assembly is provided with a series of compartments which are open on their lowermost sides and which contain air to provide buoyant lift to maintain the reflectors normally above the level of liquid in the reservoir. In an alternative arrangement, the platform assembly may be formed of or include a buoyant material. The platform assembly is rotatable about a vertical axis whilst floating on liquid in the reservoir to track movement of the sun to maintain efficient collection of solar energy throughout the day.
So as to prevent damage to the reflectors supported on the platform assembly, the platform assembly is capable of being flooded with liquid so that the reflectors are covered by a protective liquid layer. As described in my above patent application PCT/AU92/00520, to enable the platform assembly to be flooded, a pump is provided to pump liquid from beneath the platform assembly to the top side of the platform assembly. Alternatively, the platform assembly is provided with a plurality of impellers provided in ducts through the platform assembly, the impellers being capable of being driven by respective electric motors. Where a plurality of apparatuses are provided in one location associated with respective liquid reservoirs, it is necessary to provide flooding arrangements for each platform assembly which leads to complexity of the system and increased costs due to the necessity of providing liquid pumps for, and/or motor driven impellers on, each platform assembly.
In my International patent application No. PCT/AU99/00140 (AU742755), the arrangement for flooding the platform assembly which carriers reflectors or photovoltaic cells comprises means to vent the air compartments on the underside of the platform assembly to allow the platform assembly to be submerged in liquid in the reservoir. In some circumstances however, such an arrangement is not sufficient to submerge the platform assemblies rapidly which is required if there is a rapid onset of hail or other inclement weather conditions and thus a flooding system using pumps and/or impellers is preferred.
It would be desirable if an arrangement for flooding the platform assemblies of floating solar energy collecting apparatus of a solar power system was available which addressed one or more of the above disadvantages or which at least provided an alternative to the currently known arrangements.